It is known that a pump for sucking and discharging, e.g., liquid, employs a claw pole type motor with claw-shaped magnetic poles as a motor for rotatingly driving an impeller (see, e.g., Japanese Patent Laid-open Application No. 2003-505648). The claw pole type motor is simple in structure and therefore is advantageous in that it can enjoy enhanced productivity and reduced production costs thereof.
A stator of a claw pole type motor is formed of an iron core having a plurality of claw-shaped magnetic poles arranged in a circumferential direction and an annular coil received within the iron core. The iron core serves as a magnetic circuit and is formed of a molded article. Although the material cost can be saved by removing unnecessary portions, it would be undesirable if this results in deterioration of the function of the iron core as the magnetic circuit.